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Hydro Tropi Experiment Successfully Completed

Last Updated: October 26, 2010

* All times are Japan Standard Time (JST)

Hydrotropism and Auxin-Inducible Gene Expression in Roots Grown under Microgravity Conditions (Hydro Tropi)* was successfully completed.

* Principal Investigator (PI): Hideyuki Takahashi (Professor of Graduate School of Life Sciences, Tohoku University)

Hydro Tropi investigates effect of water on the orientation of root growth to clarify relation between the water and the roots.

The experiment was designed to investigate two major objectives; one is to see if roots of cucumber seedlings will bend toward water when they grow in microgravity, and the other is to identify Auxin-regulated genes.

Samples (dried cucumber seeds) were launched to the International Space Station (ISS) aboard the space shuttle Atlantis (STS-132 mission) on May 15, 2010. The experiment began aboard Kibo on October 19, 2010.

After 18 hours, a moisture gradient was artificially provided to the sponge to observe the orientation of the root growth. Root samples were collected at 18 hours, 22 hours and 41 hours after the initiation of the experiment. The samples were chemically fixed and stored in the station's refrigerator/freezer, MELFI. The experiment was completed at 0:51 a.m. on October 23, 2010.

The collected samples will be returned to the ground aboard the space shuttle Discovery, which is scheduled to launch on November 2010.

If the mechanism by which roots respond to water is understood, the nature will be applied to the root growth orientation control under a particular environment, such as development of space agriculture systems in the future.

Special Message from Principal Investigator (PI)

It has been six years since the Hydro Tropi project was selected as a candidate life science research theme for Kibo utilization. Our project has been supported by a lot of people since then. The experiment was performed without any major trouble thanks to the collaborative effort by the co-investigator and team members, who have been working at the flight control room over the past one week, and the ISS crew members, who have thoroughly performed the experiment on orbit. I look for receiving and analyzing the samples.

Hydrotropism and Auxin-Inducible Gene Expression in Roots Grown under Microgravity Conditions (Hydro Tropi)

*All times are Japan Standard Time (JST)

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